Answer
The primary cell type in connective tissue proper is fibroblast. The primary cell type in cartilage is chondroblast. The primary cell type in bone is osteoblast.
Work Step by Step
"fibro-" refers an arrangement of fibers, which most connective tissues consist of. "condro-" refers to cartilage. "osteo-" refers to bone. "-blast" simply refers a developing cell.